The present invention relates to the manufacture of electromagnetic induction devices, such as transformers, transducers and the like and, more particularly, to the manufacture of toroidally wound magnetic cores for such devices.
It is generally known that electromagnetic induction devices, such as transformers, having a toroidally wound core tightly encircling one or more wire coils of the apparatus have high efficiency, because they require less exciting current to establish a given flux as compared to cores constructed by other methods, such as E-I laminations or gapped wound cores. Such devices employing toroidally wound cores have not found wide use because of difficulties in their manufacture.
It is an object of the present invention to provide a method and apparatus for making toroidally wound magnetic cores for electromagnetic induction devices, wherein the core is formed around a pre-wound wire coil. Because of its simplicity and efficiency, this method is suitable for large-scale manufacturing operations.